Since BMT has taken the week off to take his lovely wife four wheeling (family bonding don't ya know ), I'll take a shot at this, having just installed a commercial ARB on his rig.
The main things I noticed about the ARB C as compared to my ARB (regular?) is that the approach angle is less, as the entire bar sticks out from the front end a three or four more inches. The ARB C is designed to have room for the upright Warn 8274 8K winch.
Other differences are that the middle bars are bent slightly outward, and the middle upright supports are different, both to make room for the 8274. The lower bumper is slightly wider as well.
You can get an ARB C from ARB in Seattle; however, you'll most likely have to order it and wait for the slow boat from OZ. As usual, the quality of workmanship is excellent. Welds looked great to me!
Hope that helps!
O' yeah, we're looking into making a skid plate for underneath, as there seems to be quite a bit of room, and the power steering cooling lines are somewhat exposed....
Can't tell you about price, as BMT got his second hand, but I think a new one goes for about $750 or so.
I'm back...with 1,600 additional miles on the truck and all worth it. D, Hltoppr explained most of what is different, the only other thing I have noticed is that it is a few inches narrower than the deluxe. It appears as thougth the flairs were not taken into account when the bar was designed. The ARB website claims the commercial is the lower cost, industrial version of the deluxe but when I went looking it was $650.00 plus $100.00 in shipping and I would have to wait 8 weeks. This is if you were talking to someone who knew what to look for and could find the commercial in a catalog. Its pretty gnarly though.